This support rig allows for height adjustment. The long two slanted tubes that connect the octagon to the top part the user straps into are telescoping tubes. These are photos of the different heights with me in the background as a reference. I'm 5ft 11in tall.
Above is the lowest setting I set up. More holes on the telescoping rods could be drilled to go lower by a maximum of about 5in.
Above is the highest setting. More holes cannot be drilled to increase the height.
This is the height that I personally use.